Stock agitating and circulating attachment for stock tanks used in pulp and paper mills



3 Sheets-Sheet 1 Oct. 26, 1948. J. STADLER s'rocK AGITATING AND cmcumwme ATTACHMENT FOR STOCK TANKS USED IN PULP AND PAPER MILLS Filed July 9, 1945 9 w Wi l (1 111111111045, I

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STOCK AGITATING AND CIRCULATING ATTACHMENT FOR STOCK TANKS USED IN PULP AND PAPER MILLS Filed July 9, 1945 3 She'ets-Sheet 2 DNVE NTOR Am a z mm an I l I l .2 A Q ,2 v 7 mm ////%A Om Mm AN E m m m h STADLER 2,452,399

J. STOCK AGITATING AND CIRGULATING ATTACHMENT FOR STOCK TANKS USED IN PULP AND PAPER MILLS Filed July'S, 1945 3 Sheets-Sheet 3 \NVENTOR Patented Oct. 26, 1948 STOCK AGITATING AND CIRCULATING AT- TACHMENT FOR STOCK TANKS USED IN PULP AND PAPER MILLS John Stadler, Montreal, Quebec, Canada Application July 9, 1945, Serial No. 603,948

3 Claims.

This invention relates to an improved stock agitating and circulating attachment for stock tanks used in pulp and paper mills-to prevent coagulation of the fibre bundles before the stock is delivered to the forming wire of a paper making machine.

Emcient agitation of the stock prior to its delivery to the forming wire of a paper making machine is essential to the manufacture of paper of uniform quality. This is now accomplished by the use of high speed propeller attachments arranged in a stock circulating tank to maintain the stock in a highly agitated circulating condition which eifectively prevents coagulation of the fibres or fibre bundles. Very exact workmanship is now required in the design, manufacture and installation of these propelling attachments in order to ensure the maximum efiiciency as regards agitation and circulation of the stock. In most cases where the results obtained are not entirely satisfactory the cause can be traced to defective assembly and/or installation of the attachment by careless or incompetent field workers.

At the present time propeller attachments for stock agitating and circulating tanks are installed in accordance with what may be termed open shaft practice. This consists in mounting an exposed propeller shaft in bearings carried by an outer wall of the tank and by a partition wall which isspaced from said outer wall and is provided with a flow opening in which the propeller blades operate. The bearing structure carried by the partition Wall usually includes a spider or other shaft supporting means which, by obstructing the flow through the partition opening in which the propeller blades operate, interferes with effective agitation of the stock. Another undesirable feature of the so-called open shaft installation is that the shaft is exposed throughout a substantial portion of its length to chemical attack by the stock contained in the tank.

One object of the present invention is to provide a generally improved propelling attachment of the character described which is designed to reduce to a minimum the mechanical skill required on the part of the field workman entrusted with the task of installing the attachment.

Another object is the provision of a propeller attachment of the character described in which the design and assembly of the component parts is such that the complete assembly may be supported, on the cantilever principle, solely by the outer wall of the tank in a manner which eliminates the necessity of providing a spider or other 2 flow-obstructin support at the partition openin in which the propeller blades operate.

A further object is to provide a self-contained propeller attachment of the character described in which the propeller shaft is carried by a tubular support which carries the shaft bearings, protects the shaft against chemical attack by the stock, and serves as a bearing-lubricant supply reservoir.

Other objects, advantages and characteristic features of the invention will be more readily understood from the following detailed description of the preferred embodiment shown in the accompanying drawings, in whichand the associated tank walls are shown in section.

Fig. 3 is an elevational view of the propeller blade and hub assembly forming part of the attachment shown in'Fig. 1.

Fig. 4 is an enlarged detailed view showing the manner in which the propeller blades are adjustably clamped between sections of the propeller hub to provide for adjustment of the pitchsetting of the blades.

Fig. 5 is a detail view showing one of the propeller blades appearing in the preceding figures.

Fig. 6 is a sectional view taken alon the line 6--6 of Fig. 5.

Fig. 7 is a sectional view taken along the line 'l'! of Fig. 5.

Fig. 8 is a sectional view taken along the line 8-8 of Fig. 5.

Fig. 9 is a sectional view taken along the line 99 of Fig. 5.

Fig. 10 is a development view of one of the propeller blades with data indicating the theoretical pitch.

Fig. 11 is an elevational view of the male propeller hub section.

Fig. 12 is a sectional view of the hub section shown in Fig. 11.

Fig. 13 is a view similar to Fig. 11 but' showing 3. 6 and a transverse partition 1 which conjoin y provide a tortuous or reverse flow stock circulating channel 8. The transverse partition I extends across one-half of the tank at one end of partition 8 and is provided with a flow opening 9.

The propeller attachment provided in accordance with my invention comprises a propeller shaft ll journalled in bearings 42 and II and equipped at one end with a propeller ll comprising adjustable propeller blades l5 carried by a sectional propeller hub i6 which is secured to shaft H by fastening nut l1.

Bearing i2 is located adjacent propeller hub l6 and comprises a water-lubricated composition bearing-bushing Ha contained in a tubular bearing holder iii. A flange l9 projecting outwardly from holder I8 is fastened by bolts 20 to an inwardly directed flange 2| provided at the propeller end of a tubular shaft housing 22. The other end of shaft housing 22 is provided with an inwardly directed flange 23 which is fastened by bolts 24 to a stufling box and gland assembly 25 through which shaft l I extends.

Bearing I3 is an anti-friction thrust bearing of the angular contact type and is carried by a supporting spider 21 which is fastened by bolts 28 to an outwardly directed flange 29 provided at the outer and larger end of a conical tubular insert 30 which is anchored in an opening 3| of tank wall 5 in axial alignment with the flow opening 9 of partition wall I. The inner end of insert 30 is provided with an inwardly directed flange 32 which is fastened by bolts 33 to an outwardly directed flange 3Q of bearing housing 22.

The end of shaft H which projects beyond bearing l3 may have a. V-belt pulley or a gear reducer coupling applied thereto to provide for power operation of said shaft.

The tubular shaft housing 22 is provided with a water inlet 36 to which a water supply pipe (not shown) is connected so that said housing serves as a lubricant supply reservoir for the wator-lubricated bearing bushing Ha.

From the foregoing it will be evident that shaft housing 22 and insert 30 conjointly provide cantilever supporting means for supporting the entire propeller attachment from the tank wall 5, thereby eliminating the necessity of providing, at the partition I, the usual shaft-supporting spider which, as previously stated, constitutes an undesirable obstruction of the flow opening 9.

In addition to serving as a lubricant reservoir and as a part of the cantilever shaft supporting means the tubular shaft housing 22 also serves to enclose and protect the shaft i l against chemical attack by the stock contained in the stock tank. .It will also be noted that shaft H, together with bearings l2 and i3 and shaft housing 22, may be removed without disturbing the insert 30 by removing the fastening bolts 23 and 33.

It is desirable that propeller blades l5 be adjustably mounted on propeller hub 15 so that the pitch-setting of the blades may be varied in conformity with stock consistency and power requirements to ensure the maximum efficiency underv the varying conditions encountered in mill operation. In my attachment this is provided for in a novel manner. Hub I6 is divided into two half sections comprising male section 38 and female section 38 fastened together by clamping bolts 40. Male section 38 is provided with a central sleeve extension 4! which projects through a central opening 42 of female section 39 and is mounted on shaft ll. Male section 38 is also formed with a projection 43 extending into a reassasoo cess ll provided in female section ll. The i ripheral portions of hub sections 38 and 29 are provided with mating semi-circular recesses 5 having undercut side walls 46.

A relatively large disk-shaped base 43 is cast integral with the root portion of each propeller blade I! and is fltted in opposing recesses l! of the hub sections 38 and 39, the peripheral edge of said base being bevelled as indicated at 50 to fit the undercut recess walls 46. When the bolts 40 are tightened the base 48 of each blade i5 is tightly clamped between the walls 48 of the semi-circular recesses 45 in which it is fitted and is effectively held against turning movement relative'to the hub. When it is desired to change the pitch-setting of the propeller blades this is easily accomplished by backing off the clamping bolts 40, turning the blades is relatively to the hub 16 in a pitch changing direction and then tightening the bolts 40 to clamp the blades in their new position.

It will be noted that the general design of the propeller attachment described herein enables the concentric machining of all concentric faces essential to correct alignment of the component parts to be taken care of in the shop by a skilled mechanic and the parts marked for correct fleld assembly so that the only field work requiring any skill on the part of field workmen is the comparatively simple task of correctly mounting the insert 311 in the outer tank 5. Other advantages are the protective enclosure of shaft H by shaft housing 22; the use of said housing as a lubricant reservoir for the water-lubricated shaft bearing I2 and the cantilever method of supporting the entire attachment in place so as to eliminate obstruction of the flow opening 9.

Having thus described what I now consider to be the preferred embodiment of my invention it will be understood that various modifications may be resorted to within the scope and spirit of the invention as defined by the appended claims.

I claim:

1. A stock propelling attachment for pulp stock tanks of the character described comprising a tapered, tubular member open at both ends and adapted to be fitted in an opening in the wall of the tank with the smaller end of the tubular member directed inwardly, an inwardly directed flange at the inner end of said tubular member, an outwardly directed flange at the outer end of said tubular member, an elongated tubular shaft housing provided with inwardly directed flanges at both ends and with an outwardly directed flange at one end, the last mentioned flange of the shaft housing being detachably secured to the outer side of the inwardly directed flange of said tubular member, a shaft bearing detachably secured to the inwardly directed flange at the free end of said shaft housing, a stufling box detachably secured to the inwardly directed flange at the opposite end of the shaft housing, a spider detachably secured to the outwardly directed flange of said tubular member, a bearing supported by said spider in alignment with the first mentioned bearing and the stumng box, a propeller shaft extending through said bearings and stuffing box and a. propeller mounted on an end portion of the shaft projecting beyond the free end of the shaft housing.

2. A stock propelling attachment as set forth in claim 1, in which the component parts of said attachment are mounted on concentrically machined faces to ensure correct alignment of said 2,4sa,sce

faces during field application of said propeller assembly to said tank.

3. A stock propelling attachment for pulpstock tanks of the character described comprising a tubular member open at both ends and adapted to be fitted in an opening in the wall of the tank, a tubular shaft housing having one end detachably secured to one end of said tubular member, a shaft bearing detachably secured to the free end of said shaft housing, a stufling box detachably secured to the opposite end of said shaft housing, a second shaft bearing detachably secured to the end of said tubular member remote from said shaft housing, a propeller shaft extending through said shaft bearings and said stufling box and projecting beyond said shaft bearings and a propeller secured to a portion of the shaft projecting beyond the free end of said shaft housing.

JOHN swam-m.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

